Vasyliev V. Phase composition, physical and mechanical properties of composite nanostructured coatings based on nitrides of refractory metals

The dissertation is devoted to reveal of structure and properties formation mechanism of Ti-N, Ti-Al-N and Ti-Al-Y-N coating systems, deposited with using a new high-productive filtered vacuum-arc plasma source. It was described the plasma source developed with rectilinear type filter, which provides the uniform distribution deposition rate of 15-20?m/h on the 18cm diameter at the 15cm distance from the filter. It was defined conditions for obtaining the hard (28-36GPa) nitride coatings with a cubic structure such as NaCl, providing improved tribological properties of the coatings and their resistance to cavitation and abrasion wear. It was found that at constant potential bias up to -150V in coatings are formed the texture with the direction of an axial axis [111] normal to the surface. Applying of the pulse bias potential with amplitudes ranged in 0.5…2.5kV region leads to a change of the texture axis on [110] and formation of uniform coating microstructure at smaller size of coherent scattering regions (CSR). It was revealed that such structural changes provide significantly better the coatings protective properties. The width and depth of wear tracks at tribological tests of TiN coatings, deposited under pulsed potential, in 3-4times less than at the constant potential, and the friction coefficient did not increase during the tests and remains on level of 0.1-0.2.